Learn French: Je travaille jusqu'à midi.

While pendant means for or during a set length of time (like for three hours), jusqu'à means until a specific endpoint. Since midi (noon) is the exact time the work stops, rather than an amount of time, we use jusqu'à.

Where does the apostrophe in jusqu'à come from?

It is a contraction of the word jusque (which means until or as far as) and the preposition à (to or at). Because à starts with a vowel, the e in jusque is dropped to make it flow better, becoming jusqu'à.

Why is there no article like le before midi?

When referring to noon (midi) or midnight (minuit) as specific times on the clock, French drops the article. You treat it just like a specific hour, so it is simply jusqu'à midi instead of jusqu'à le midi.

Can I use the near future tense here and say Je vais travailler jusqu'à midi?

Yes, you absolutely can! Just like in English, you can use the present tense for an action happening right now that will continue until later, or you can use the near future to say I am going to work until noon. Both sound perfectly natural in French.